title: Radiopacity and histological assessment of Portland cement plus bismuth oxide.
abstract: OBJECTIVE
  The present study evaluated the subcutaneous connective tissue reactions and the radiopacity of MTA, Portland cement (PC), and Portland cement plus bismuth oxide (BO).
  
  
  METHODS
  Forty rats were divided into 5 groups (n = 8 per group): A1: Control (empty capsule); A2: Pro-Root MTA; A3: PC; A4: PC + BO 1:1; and A5: PC + BO 2:1. Polyethylene tubes were filled with the test materials and standardized radiographic images were taken. Histological evaluation was done after 7 and 60 days. Student t test and Fisher's test were used in the statistical analysis (P < .05).
  
  
  RESULTS
  The radiopacity of the materials were in decreasing order: A2 > A4 > A5 > A3. No differences were found for the tissue response in the 2 experimental periods. A positive correlation between BO concentration and radiopacity of PC was determined.
  
  
  CONCLUSIONS
  The histological evaluation suggests that all studied materials were biocompatible at 7 and 60 days.
authors.affiliation: Department of Endodontics, Rio de Janeiro State University, Rio de Janeiro, Brazil.
authors.forename: Tauby
authors.initials: T
authors.lastname: Coutinho-Filho
authors.forename: Gustavo
authors.initials: G
authors.lastname: De-Deus
authors.forename: Leila
authors.initials: L
authors.lastname: Klein
authors.forename: Gisele
authors.initials: G
authors.lastname: Manera
authors.forename: Carla
authors.initials: C
authors.lastname: Peixoto
authors.forename: Eduardo Diogo
authors.initials: ED
authors.lastname: Gurgel-Filho
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry / Q000633:toxicity; D000818:Animals; D001729:Bismuth / Q000633:toxicity; D017610:Calcium Compounds / Q000737:chemistry / Q000633:toxicity; D003238:Connective Tissue / Q000187:drug effects; D003287:Contrast Media; D003738:Dental Cements / Q000737:chemistry / Q000633:toxicity*; D004338:Drug Combinations; D007249:Inflammation / Q000139:chemically induced; D008297:Male; D010087:Oxides / Q000737:chemistry / Q000633:toxicity; D051381:Rats; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000633:toxicity*; D017640:Silicates / Q000737:chemistry / Q000633:toxicity; D040521:Subcutaneous Tissue / Q000187:drug effects
chemical_list: D017607:Aluminum Compounds; D017610:Calcium Compounds; D003287:Contrast Media; D003738:Dental Cements; D004338:Drug Combinations; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; C472247:accelerated Portland cement; C086631:mineral trioxide aggregate; C033301:bismuth oxide; D001729:Bismuth